The second and more controversial argument about section 4 was that if Congress refused to act, the president had authority unilaterally to raise the debt ceiling by instructing the secretary of the Treasury to issue new bonds without congressional approval. This argument is more of a stretch. Article I, section 8 of the Constitution gives Congress, not the president, the authority to borrow on the credit of the United States. The best version of the argument would be that the president has been caught in a catch-22: Congress has ordered him to spend appropriated money, but it has forbidden him to issue new debt to do so. If these contradictory commands would cause the president to violate section 4, then he has a constitutional duty to treat at least one of the laws as unconstitutional as applied to the current circumstances. The president could therefore treat the debt ceiling limit as unconstitutional and order the Treasury to issue new debt. However, even if the president had this authority, it would only exist if he had no other practical alternatives to issuing new debt. It is likely that the president would have some alternatives. Moreover, as explained below, things would probably never come to that point.
It is worth noting that President Obama -- again, much to the chagrin of many members of his party -- seemed eager to avoid turning the dispute into a constitutional question. He denied that he had constitutional authority to raise the debt ceiling by himself. In fact, Obama actually wanted to be painted into a corner: He thought he could achieve a grand bargain on debt reduction with congressional Republicans. Invoking section 4 would absolve them of any responsibility to negotiate in good faith. Bill Clinton, by contrast, argued that Obama should not have taken this possibility off the table. He should have threatened to invoke the 14th Amendment early on, and dared the courts to tell him otherwise.
These interesting constitutional questions were not resolved by the debt-ceiling crisis. They are unlikely to be resolved in the future, and for a fairly straightforward reason. Consistent with the government's duties under section 4 of the 14th Amendment, the Obama Administration calmly informed bondholders that no matter what happened, they would be paid on time. Giving priority to bondholders meant that some government programs would not be funded, which would inevitably lead to a partial government shutdown. Once the shutdown began, it would be more or less a replay of 1995. Both sides would quickly reach an agreement to raise the debt ceiling, and, once again, it is likely that the Republicans in Congress would take most of the blame for the fiasco. (Moreover, if the shutdown continued, the markets might also begin to decline precipitously, making an agreement even more urgent.) Knowing this, congressional Republicans had good reason to agree to raise the debt ceiling before a shutdown occurred, and that is precisely what happened.
For this reason, the debt-ceiling crisis was a phony crisis, entirely self-inflicted. There was little doubt, at the end of the day, that the president and Congress would agree to raise the debt ceiling. The only issue was the price that would be exacted, and how much damage the economy would suffer in the interim. Moreover, both the president and Congress negotiated against the backdrop of the expiration of the Bush tax cuts in January 2013, which would go a long way toward resolving current concerns about the deficit.